Chronic heart failure is one of the leading causes of morbidity and mortality in the United States. Although the mechanisms of heart failure (HF) have been studied extensively, mortality remains high and the aim of HF treatment in the clinic is focused on relieving symptoms, preventing hospitalization, and improving the quality of life of the patient. Four categories of drugs, including diuretics, inhibitors of renin-angiotensin-aldosterone system, beta-adrenergic receptor blockers, and cardiac glycosides, are currently recommended by The American College of Cardiology/American Heart Association Joint Guidelines for routine use to treat HF. Hunt, S. A., et al., Circulation 112(12):e154-235 (Sep. 20, 2005). Among these drugs, cardiac glycosides, including, but not limited to, digitoxin, digoxin, and ouabain, have been used for more than 200 years with multiple beneficial clinical effects. Treatment with digoxin can improve symptoms, increase cardiac output, enhance the quality of life, decrease cardiac decompensation, and decrease the need for and/or duration of hospitalization. The clinical use of digoxin has waned in recent years; however, due to its potentially toxic side effects and the finding that long term mortality is not significantly reduced.